"She is really courageous. I know that she is fighting the good fight and I think about her all the time and I send my prayers to her," Carteris told us. "She is really rising to the occasion in terms of really taking care of herself and fighting the fight." Gabrielle continued, "She is really reflective of what I hope signifies her getting better and getting through it. She's a fighter."

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Tori Spelling has also spoken openly about her admiration for Shannen's perseverance during the understandably difficult chapter in her life.

The actress and reality TV star recently opened up to E! News about Doherty's illness, revealing, "We've all been talking and supporting her from afar. It's really hard to know what to do when someone's going through that—if they want people there or not there. But I think she's very brave and I admire her so much."

In late November, Doherty began radiation, another step in the treatment process she hasn't shied away from sharing with fans on social media. Since then, the 45-year-old has offered glimpses into all the ups and downs she's faced along the way.

Alongside one video of herself working up a sweat in a dance class, Doherty wrote, "It's so easy to get depressed in the battle against cancer but everyday I wake up and remind myself to be happy to be alive, relatively healthy and able to move. I'm so thankful for this life I have."